How to : PANORAMAS : 360 Photospheres

Pinnacles of Adventure Photosphere

Pinnacles Desert, Western Australia


Good day. Over the past few months, I've been driving around to some iconic locations along the West Australian coast at night to capture 360 degree photospheres, showing the beauty of dark skies above the Australian landscape. 

I've found that photospheres are an effective way to enable the viewer to experience what it is like to be there for themselves. Coupled up with a VR headset, photospheres are truly an immersive way of experiencing Astrophotography.

In this post, I'll be writing on how I prepare, stitch and project my 360 photospheres. The image that we will be working on consists of 80 individual images shot in a 10 x 8 grid in landscape orientation with each image being overlapped by 50%. 

The most important thing to remember in photospheres is to shoot a full 360 degree by 180 degree to ensure a 2 x 1 aspect ratio for the final image.

It was shot using a Nikon D750 DSLR, Sigma 24mm ART lens and a Gigapan Epic Pro panorama mount. Total shooting time was around 40 minutes.

Settings:

ISO 3200

F1.8

25 seconds x 80 frames

Here's the layout of how the images were shot.


Preparing the RAW files

Before we stitch and project our images, we need to prepare the RAW files by correcting the White Balance, Lens Distortion, Lens Coma, Lens Vignetting and add some Noise Reduction. These steps will help us a lot in the stitching process by removing any image artifacts which puts less stress on the stitching software.

First import all the images to Lightroom and click on the "Develop" module to process the images. 

Once in we're in the Develop Module, we can start with the Lens corrections. I tend to work on a single image that contains the Milky Way core to get an accurate White Balance. We generally want the core to be pale yellow in colour. 

Let's remove the vignetting and lens distortion by enabling the Profile Corrections. Ensure that the "Remove Chromatic Aberrations" box is checked as well.

Now that we have a flat and evenly exposed image, we will go ahead with the White Balancing. The way we do this is to slide the "Vibrance" and "Saturation" sliders to +100 to have a look at what colours data was captured in the image. 

As you can see, we have far too much blue and magenta in the SOOC shot. We generally want the core of the Milky Way to be pale yellow and the rest of the sky to be a good mixture of green and magenta. 

Slide the Temp and Tint sliders until we achieve the desired White Balance. 

Once we are satisfied with the White Balance, we can reset the Vibrance and Saturation sliders back to 0. 

The next thing we need to do is a minor technical clean up by removing the default sharpening that Lightroom applies to all images and add some minor noise reduction.

Our image is now ready to by stitched, we just need to sync the settings to the rest of the images and export them in the correct format. 

Finally, we can export our images with the following settings: (Note that I downsize my images from 24mp to 12mp to save on storage space)


Stitching and Projection

My preferred stitching software is Autopano Giga. However, Microsoft ICE will do the job as well. 

If you need a detailed guide on how to stitch images in Autopano Giga, I've written one here.

Ensure the image is projected as a Spherical projection.

The spherical projection is a 2D representation of a 3D sphere. The distortion towards the top and bottom of the image is a result of this projection, not lens coma or aberrations, and is perfectly normal. 

Render the image as a 16bit TIFF file.


Lightroom Processing and Export

Import the stitched image into Lightroom for processing. Ensure the final image is in 2 x 1 aspect ratio or the image will not be projected as a sphere.

Finally! We can export our photosphere. Export the image as a JPEG at 300dpi and ensure that the long side of the image is no wider than 12000 pixels. This is because Google Street View doesn't allow images wider than 12000 pixels.

If you want to upload your image to Facebook, this limitation does not exist.


Upload to Facebook or Google Street View

And we're done! Upload the exported image to Facebook or Google Street View and it will automatically recognize it as a 360 Photosphere!

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How to : PANORAMAS : Stitching

Have you ever felt that a 14mm F2.8 Rectilinear lens on a Full Frame DSLR just wasn't wide enough?

Have you ever wanted to shoot wider than the field of view of your lens?

You can... with a 24mm.

 

Welcome to ASTRORDINARY Imaging. My name is Paean Ng, a self-taught astrophotographer based in Perth, Western Australia.

I've recently been asked by several people to write tutorials on how I produce my images. So here's the first tutorial in a new "How to" series.

I've been using the Sigma 24mm F1.4 ART lens along with a Nikon D750 as my main shooting combo for the past year and have come to know this particular set up intimately. Along with my Gigapan Epic Pro, this is the main set up I use to shoot panoramas and photospheres.

People prefer different looks to their photos. Some like the standard 50mm perspective and some like the ultra-wide and distorted perspective. It's important to know, however, that the perspective of the resulting panorama will be the same as the perspective of the lens it was shot on. In other words, stitching multiple images shot on a 24mm will NOT result in an image that looks like a 14mm. It will just look like a very wide 24mm perspective. 

With that being said, I like the 24mm perspective because it's the widest angle in the standard 24-70 field of view. 

Lets jump right in. I'll be basing this tutorial on a panorama I shot at Sugarloaf Rock, Dunsborough.

This is the equipment and settings that were used. 

Equipment:

Nikon D750

Sigma 24mm ART

Gigapan Epic Pro

Shooting Settings:

ISO 3200

F2.0

20 seconds

35 frames. (7x5 grid in landscape orientation)

Before the stitching process begins, I first prepare the images by importing them into Lightroom and applying the appropriate Lens Correction Profiles and roughly change the White Balance of the image. Sync the changes throughout all the images and export them as 16bit TIFF files.

My preferred stitching software is Autopano Giga. It's extremely powerful and really simple to use, but it does cost. A free alternative is Microsoft ICE. You won't have all the functionality of a paid product, but it works. 

 

Import the prepared images into Autopano Giga and click "Settings", which is the Spanner icon next to "Detect". 

 

These are the settings I use. I find that keeping the "Detection" on automatic works best.

 

Ensure all colour corrections options have been turned off. 

 

Once all the settings are correct, go ahead and click the "Detect" button and let Autopano Giga do it's thing. Once the initial detection is done, you will be see something like this:

Double click on the projected image on the right to bring up the Edit screen. If the image looks distorted, split, incomplete or anything else that might get you worried, relax, its normal. We'll fix it.

 

Use the "Move" tool to reposition the image until it is centered.

 

By default, Autopano Giga will project the image as a Spherical projection. You can change the way the panorama is projected by changing the Projection Settings:

The Projection I use most is "Little Planet" with a locked Horizon. This style of projection is the same as a Stereographic projection in Microsoft ICE and PTGui. Play around with the different projections and you might find something you like. 

Now we need to resize the projection by sliding the "Squeeze" button up to around 0.35 and crop out the unwanted parts. 

Now we have a working image, scaled to the correct size and roughly cropped to what we want. If the panorama was shot correctly, you shoudn't run into any stitch errors. If you do have errors, however, they can be fixed by manually adding control points by clicking on the "Control Point" button.

If you find a stitch error in the sky, don't bother correcting it. There are thousands of stars in each frame, I doubt a minor stitch error is going to make a difference to that.

Once you're satisfied, render the image with the following settings and then import it to Lightroom.

Ensure the image is rendered as a TIFF file at 16bits, 300dpi to maintain all the RAW goodness for processing in Lightroom.

Final Edit.

 

There we go, that's the way I stitch my panoramas. I hope this guide was useful. Please leave a comment and follow me on facebook. www.facebook.com/astrordinary

 

 

Paean Ng